diff options
author | ru <ru@FreeBSD.org> | 2003-06-28 23:53:39 +0000 |
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committer | ru <ru@FreeBSD.org> | 2003-06-28 23:53:39 +0000 |
commit | 348e423dd913fabaea56f15eecca3d155723ee08 (patch) | |
tree | 119cebb3a669617b213ec04fe871163ae082cfb1 /share/man/man4/inet.4 | |
parent | e4f0eb6b17525e227a1bc1d660ab253005530425 (diff) | |
download | FreeBSD-src-348e423dd913fabaea56f15eecca3d155723ee08.zip FreeBSD-src-348e423dd913fabaea56f15eecca3d155723ee08.tar.gz |
Hiten's patchset for section four manpages, slightly edited by me.
Diffstat (limited to 'share/man/man4/inet.4')
-rw-r--r-- | share/man/man4/inet.4 | 41 |
1 files changed, 25 insertions, 16 deletions
diff --git a/share/man/man4/inet.4 b/share/man/man4/inet.4 index d15c204..3296a39 100644 --- a/share/man/man4/inet.4 +++ b/share/man/man4/inet.4 @@ -61,7 +61,8 @@ Internet addresses are four byte quantities, stored in network standard format (on the .Tn VAX these are word and byte -reversed). The include file +reversed). +The include file .Aq Pa netinet/in.h defines this address as a discriminated union. @@ -116,7 +117,8 @@ abstraction while .Tn UDP is used to support the .Dv SOCK_DGRAM -abstraction. A raw interface to +abstraction. +A raw interface to .Tn IP is available by creating an Internet socket of type @@ -126,7 +128,8 @@ The message protocol is accessible from a raw socket. .Pp The 32-bit Internet address contains both network and host parts. -However, direct examination of addresses is discouraged. For those +However, direct examination of addresses is discouraged. +For those programs which absolutely need to break addresses into their component parts, the following .Xr ioctl 2 @@ -148,7 +151,8 @@ Get interface network mask. .Sh ROUTING The current implementation of Internet protocols includes some routing-table adaptations to provide enhanced caching of certain end-to-end -information necessary for Transaction TCP and Path MTU Discovery. The +information necessary for Transaction TCP and Path MTU Discovery. +The following changes are the most significant: .Bl -enum .It @@ -160,11 +164,12 @@ flag forcibly enabled (they are thus said to be .Dq "protocol cloning" ) . .It When the last reference to an IP route is dropped, the route is -examined to determine if it was created by cloning such a route. If -this is the case, the +examined to determine if it was created by cloning such a route. +If this is the case, the .Dv RTF_PROTO3 flag is turned on, and the expiration timer is initialized to go off -in net.inet.ip.rtexpire seconds. If such a route is re-referenced, +in net.inet.ip.rtexpire seconds. +If such a route is re-referenced, the flag and expiration timer are reset. .It A kernel timeout runs once every ten minutes, or sooner if there are @@ -177,13 +182,15 @@ net.inet.ip.rtexpire if the number of cached routes grows too large. If after an expiration run there are still more than net.inet.ip.rtmaxcache unreferenced routes remaining, the rtexpire value is multiplied by 3/4, and any routes which have longer -expiration times have those times adjusted. This process is damped -somewhat by specification of a minimum rtexpire value +expiration times have those times adjusted. +This process is damped somewhat by specification of a minimum rtexpire value (net.inet.ip.rtminexpire), and by restricting the reduction to once in a ten-minute period. .Pp If some external process deletes the original route from which a -protocol-cloned route was generated, the ``child route'' is deleted. +protocol-cloned route was generated, the +.Dq child route +is deleted. (This is actually a generic mechanism in the routing code support for protocol-requested cloning.) .Pp @@ -195,7 +202,8 @@ external routing process, or under the management of a link layer for Ethernets). .Pp Only certain types of network activity will result in the cloning of a -route using this mechanism. Specifically, those protocols (such as +route using this mechanism. +Specifically, those protocols (such as .Tn TCP and .Tn UDP ) @@ -221,7 +229,8 @@ Boolean: enable/disable the use of fast IP forwarding code. Defaults to off. When fast forwarding is enabled, IP packets are forwarded directly to the appropriate network interface with a minimal validity checking, which -greatly improves the throughput. On the other hand, they bypass the +greatly improves the throughput. +On the other hand, they bypass the standard procedures, such as IP option processing and .Xr ipfirewall 4 checking. @@ -250,12 +259,12 @@ Boolean: enable/disable forwarding of source-routed IP packets (default false). .Pq ip.rtexpire Integer: lifetime in seconds of protocol-cloned .Tn IP -routes after the last reference drops (default one hour). This value -varies dynamically as described above. +routes after the last reference drops (default one hour). +This value varies dynamically as described above. .It Dv IPCTL_RTMINEXPIRE .Pq ip.rtminexpire -Integer: minimum value of ip.rtexpire (default ten seconds). This -value has no effect on user modifications, but restricts the dynamic +Integer: minimum value of ip.rtexpire (default ten seconds). +This value has no effect on user modifications, but restricts the dynamic adaptation described above. .It Dv IPCTL_RTMAXCACHE .Pq ip.rtmaxcache |